How is she doing in school? How is she doing in background noise?
Given a new diagnosis I might retest at 6 months in a child, but I’m conservative. Annual is probably fine. But take this time to ask around and find out who the best pediatric audiologist in your area is. Sources of information on that might be the educational audiologist or itinerant teacher of the deaf and hard of hearing connected with the school, might be parents of other children in the area with hearing loss, might be your family doctor.
We do genetic testing for newly diagnosed children where I am, but I know it’s not available in all areas. You could ask her doctor. It’s not necessary, but some families like to know what to expect from the hearing loss, which knowing the genetics sometimes helps (though etiology cannot always be identified). If a known genetic cause can be identified it sometimes also helps to identify other things that sould perhaps be monitored. It may suggest whether or not the loss will be progressive. For example, genetics on a recently diagnosed child were able to say that her type of loss appeared between the ages of 4 and 10 and that her siblings had a 50% chance of the same loss but not after the age of 10. So, typically not information that affects treatment, but information that can be helpful.
But you are very early. You’ve done the right thing to follow-up and get her tested, and now she will not be missed and will get timely intervention when she needs it. That’s excellent.